


Liquid Mercury

by WormholesandPegasus



Category: Percy Jackson and the Olympians & Related Fandoms - All Media Types, Percy Jackson and the Olympians - Rick Riordan
Genre: Alternate Universe - Canon Divergence, But Also An AU, Character Study, Dark, Gen, Light Angst, Luke leaves camp a lot sooner, Luke-centric, Pre-The Lightning Thief (Percy Jackson), Roman!Luke, but not really, no beta we die like men
Language: English
Status: Completed
Published: 2020-08-13
Updated: 2020-08-13
Packaged: 2021-03-06 07:41:38
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,929
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25879849
Author URL: https://archiveofourown.org/users/WormholesandPegasus/pseuds/WormholesandPegasus
Summary: Luke knows he doesn’t fit at Camp Jupiter, but that won’t stop him from achieving his goals and tearing Olympus to the ground.In which everything falls apart much sooner.
Comments: 2
Kudos: 21





	Liquid Mercury

**Author's Note:**

> I wrote this in like a few days, so let me know if I made any errors, I’d be happy to correct them.

Luke watches.

The campers stand on Half Blood Hill, doing nothing. Nothing to save Thalia.

So Luke does what the others refuse to do: take action. He picks up Annabeth, and sprints with the speed of his father towards the group of campers. He will do anything he can help. It is never enough. Because the look in Annabeth's eyes as she watches Thalia die hurts him deep inside in a way he'll never forget.

The echoes of his friend's dying breaths inter spaced with his own footfalls will haunt him for the rest of his life.

There is not much arrival fanfare after that. Chiron tells him that Thalia has been turned in to a tree.

"What do you mean she was turned into a tree! She died!" The veins in Luke's neck stand out, red and angry.

Chiron chooses his words carefully. "Her father decided to spare her." 

Spit flies from Luke's mouth, "Then why isn't she standing with me right now! Spare her? Then why didn't he save her months ago when we were starving?"

The centaur does not provide a response. 

It doesn't matter in the end, Annabeth is safe. But something inside of Luke gets sick whenever he stands in the open grass looking at Thalia's tree.

Luke learns swordsmanship from a child of Ares. The sword feels so natural in his hand. It fits.

On the way back from practice a camper remarks that the boundaries are protected now. He seems almost happy. It is then that Luke realizes half of the camp didn't even know her name. It's wrong.

But he says nothing, only watches.

And so Luke disappears from Camp Half Blood two weeks later.

Annabeth Chase stands outside the Athena cabin, stuffed animal in hand watching her last remaining friend leave her behind.

After two months Luke has crossed the country with stops in Orlando, Chicago, Dallas, and Vegas. His most interesting stop is training with a wolf somewhere in the north. His money runs out somewhere in Northern California.

Coincidentally that is when the empousas start to follow him. He never attracted monsters before on his own. That was always Thalia. Not that it was her fault. 

Still, something isn't right.

Luke smiles at his enemies, blood on his bared teeth. He goads the monster, "You seem like a familiar face. Have we met before? Perhaps at a family reunion." 

The lead empousa snarls. "You will die where you stand."

"I've got places to be, my friend. I'm afraid I cannot commit to that." Sickly sarcasm oozes from his statement.

"We won't let you get to safety."

It appears Luke has inherited something from his father the trickster god. He got the answer he needed. 

The empousa are doing there best to push him away from the freeway. Something is down there that Luke is not supposed to see. So of course he will go that way. He has no other option.

Luke heads towards the freeway where he can see two guards not much older than himself. Deep down something clicks and he knows they are like him.

His legs start to move faster and faster, constantly increasing their speed as Luke crosses the highway at inhuman speeds. He passes the guards who stand aside as Luke's legs continue to carry him. The world blurs and his mind focuses on safety. If only he could have had this speed when Thalia needed him.

But just as he reaches the water, he stops. Luke cannot bear to endanger the others in the camp. He will not create more Thalias.

The empousa do not know what hit them.

Luke Castellan crosses the Little Tiber the day before he turns fifteen, greek sword in hand. 

He is greeted as a hero.

He watches the campers closely. It's very different from his reception at Camp Half Blood, Camp Jupiter is joyous. They celebrate a new brother added to their ranks.

Almost immediately Luke knows he is not Roman. He is and always has been Greek.

The people at Camp Jupiter are too stiff, too regimented to be anything like the people of Camp Half Blood. Luke knows he does not fit in either place, but he can fake it. His father is the patron god of liars and cheats. He'll do just fine.

The praetors have many questions, and Luke has answers—they are not the whole truth but they are true. He stole his sword, he has not been officially claimed, he knows his father is the god of messengers, he traveled across the country, he parted ways with his friends over a month ago, he met Lupa, he defeated the empousa.

It's enough to bait Aurem and Argentum. Luke calls that a victory.

He is settled into the second cohort after a week of being a probatio. Mercury's children aren't strong, trustworthy, or important enough for the first cohort. Luke files that information away to process later.

The most important thing Luke has learned, however, is that the Romans hate the Greeks. Luke will likely be killed if he is found out. He can't let that happen.

Over that time he gets the tattoo. His father is only there for a minute. He answers none of Luke's question. All Luke is left with is the sad look in his father's eyes.

His first war games occurs that evening.

It's an exhilarating rush of power and danger. Speed, ferocity, rage. Luke loves every second of it. 

He makes the decision then.

Luke chooses to stay year round. New Rome has a program that trains their legionnaires over the winter in things that are more than just fighting. Math, geography, history, Latin.

Luke pushes his emotions down like he always does. Camp Jupiter may be a mess of rules but it is a place where Luke can become great and that is enough.

There's a little boy aiming to be an augur at the first meeting of the full legion for the year. 

Luke watches the probatio—who is much too young to be a legionnaire. The kid is eight and a legacy of Apollo but it still looks as if he will be put in the first cohort when he is old enough. Why legacies, who have the ability to live a normal life stay at Camp Jupiter is beyond Luke. As is why legacies are given preference to the first cohort over children of Mercury.

As with Camp Half Blood, their rules don't make sense. Luke doesn't care enough to try to understand their reasoning.

His mind returns to the announcements. None of them have mattered until now. But this one is important, a new quest for a daughter of Mars in the first cohort. 

Luke wasn't chosen for a quest last summer, but he has proven himself in the time since then. 

Nothing. Luke gets nothing.

He shouldn't be surprised. He's a son of Mercury, who would trust him?

It is a month before the next quest. No one has heard any word from any of the questers. Complete radio silence.

They are presumed dead.

The new quest is for a son of Ceres in the third cohort. He's desperate, the last quest was a failure and he is in a lower cohort. Most quest leaders try to work within their cohorts.

The boy makes eye contact with Luke and gasps out his name.

Luke accepts, he's already crossed the country unprepared. How different is this from then? At least now he has a goal, that is an improvement.

The boy's name is Mark. Their other companion is a girl from the fourth cohort called Lauren.

They are to travel to Louisiana and look for a blessed laurel tree somewhere in the bayou. The quest is vague to say the least, a suicide mission would just about cover it.

The questing group takes a bus south. Phoenix, Austin, Baton Rouge all go by in a haze. All they get is sleep.

Finally, they reach their stop. New Orleans, Louisiana.

It's the first time Luke has been to New Orleans. It's full of lights and music. It's so beautiful. He can't believe it. He doesn't ever want to leave. It's his personal paradise.

Luke cries that day.

The days in the bayou are a lot harder. Muddy, dark, disgusting. And the monsters are plentiful. They swarm the demigods.

It's a lot worse than his time with Thalia. There are many monsters and many more distractions.

The final battle is a bloodbath.

Mark sacrifices himself fighting their final monster and Luke is forced to watch. He does his best to keep the sounds of Thalia's last moments out of his head. 

Poor Lauren took a monster claw to the leg. She's very badly injured and Luke has to carry her out of the bayou by himself. She cries softly as if that will make Luke not hear it. He doesn't say anything, the girl is so brave.

Luke carries her back to camp too. Their medicine is not enough for her to heal before they return.

Camp Jupiter treats him as a hero. He arrives to celebration and fanfare. But it's not for Mark, this time it is for Luke.

Something deep inside of Luke snaps. Mark and Lauren have been pushed to the side. The quest was a tragedy, not a success. Mark died and Lauren could be permanently injured and the camp does not care about them. Luke is the first person to visit Lauren in the med tent a day after the quest. He cannot imagine what the girl is thinking.

But the most shocking thing is his father. He gets a single note from the messenger god, one of congratulations and praise. He was too busy to come. Somehow that is the worst option.

Luke crumples up the note in his fist. The thought to throw it out flashes through his mind. But he dismisses it. It won't be useful to him that way. He shoves it in his pocket.

Because he knows he can no longer trust the gods or his peers. The world is a mess and Luke aims to fix it.

A new voice enters his dreams that night. 

After the retirement of Warren Price at the end of the summer, Luke is appointed centurion of the second cohort.

He's a hero—but at what cost? He asks himself that question every day until it burns itself into his brain.

Luke has all the time in the world to make connections. He's a hero, he can change the world. He can fix all of their problems, and all he needs to do is just talk.

It is going to be a long year.

Luke talks and talks. The praetors become his close friends. The senators his brothers and sisters. He becomes an integral part of the system. A parasite.

He watches the senate meetings before he becomes one of them. That takes the winter. 

Luke is advancing rapidly. The others can tell. Some are even unnerved.

The legacy Luke remembers from last year is suspicious of him. That alone should make the demigod laugh. A child making speculations at his motives. It's a joke.

However, the voice in his dreams won't let him brush that aside. Luke is asked to do the unforgivable. He almost doesn't do it but it is his life at risk as well. He can't let a boy and his stuffed animals give him up as a Greek.

Luke greets the boy at the barracks and asks for a walk. An offer, he calls it. He hopes the boy assumes it is a request to join the second cohort.

No one is in the barracks when he leaves, and he hopes no one sees their walk to the shore.

"Look, I appreciate your offer, but my plan is to join the first cohort as my father did."

Luke does his best to keep a sneer off of his face. Octavian disgusts him. A privileged little kid who thinks he is better than all the rest of them. "And why is that set in stone?"

"I want to be an augur. Camp Jupiter has not had one in years." The boy speaks as if he is looking down on the centurion.

Luke sighs, "Maybe you can still do that if you shut your little mouth, my friend." 

The casual tone sets Octavian off guard. "What do you mean?"

Luke smirks, "What I said." 

He turns his back on the scene, leaving the little boy to interpret his message alone. It doesn't take him long.

Octavian never speaks out against Luke again. Whether that will be for the best remains unclear.

Later that night Luke stands all alone in the darkness of the new moon, on the far side of the Little Tiber and pledges his undying loyalty to Kronos. Not one person witnesses the ritual.

Almost nothing changes, the world goes on. Luke takes that as proof of the cause.

The next exciting event happens when Luke is seventeen and has three bars. He is called on to lead a quest.

It's not a repeat. It's something new.

Luke is called to restore one of Venus's monuments in the desert. It will be short but it is a quest none-the-less. He knows he should be excited—it's his second quest after all—but he isn't. Maybe something is wrong with him. 

But he has another idea. Luke has a purpose now, and it isn't one that was given to him by the gods.

He picks two teens: Nikki, daughter of Apollo, and Gina, daughter of Vulcan. Both of them are in the second cohort and a year or two younger than Luke. It may be their last chance to go on a quest. 

But Luke isn't choosing the two out of pity, both are extremely qualified for this quest and Luke as their centurion knows this very well.

Their path is unclear as the whole quest is. The item they need to restore is a bracelet of Venus, broken into two pieces. One to be found in a hidden lake where the land meets the sky and ice's rule is set to expire, the other where monuments of sand still stand. 

The southern piece is obvious to Nikki. The sixteen-year-old lives in New Mexico with her mother, a painter who hikes for the vistas. She's been to Monument Valley state park in Arizona at least ten times. 

"It has to be there!" She says.

And she is right. That doesn't make the quest any easier. It certainly does not stop the snakelike monsters from attacking them.

They finish their first major fight bloodied but alive. For the first time in a long time Luke feels some hope within him. He sleeps well that night at the motel.

But it doesn't take long for the sinking feeling to return. The second half of the quest will be much harder, he knows it.

Gina breaks her spear traveling north. The questers use some duct tape to patch it up. Somehow it still works, that is a miracle in and of itself. He still won't call it a blessing.

The road is long. Nikki is sixteen so she can legally drive, but Gina is fifteen and none of them want to be pulled over, they have enough on their plates. They agree to not have her drive unless it is necessary. So Luke and Nikki take shifts.

The spend their next night in Salt Lake City. It's a lot colder than Luke expected. It snows overnight.

Luke unloads the two girls out of their Camp Jupiter issued SUV for a cheeseburger somewhere in the middle of nowhere Montana. Apparently it's the best burger in Broadwater county.

They've been there for half an hour when another group of young people enters the restaurant. The kids seat themselves halfway across the restaurant.

Luke is able to watch their lively banter from where he is sitting. It is very enjoyable to listen to. No one but Luke would understand it. The are demigods, Greek demigods. Luke can't believe it. He never thought he'd see one of them again in his life. He almost laughs—the key word being almost.

Two boys and a girl sit at a booth against the window. They're all under fifteen. That fact makes Luke sick to his stomach. 

Nikki and Gena have noticed his thousand yard stare by now. They've seen it a hundred times before. 

"We'll pack up," Gena says. "Meet us in the parking lot when you're ready." She has always been nice.

A minute passes before Luke wanders over the table, all the different things he could say rattling through his skull. And yes, he is completely aware he looks like a zombie. 

The greek campers are aware as well. Luke can see all of them tense up, the older boy even grabs the hilt of his sword.

Luke throws his hands above his head at the show of aggression. "Hold up, hold up. I'm not here to hurt you." 

They are still suspicious.

"I'll prove it." Luke has absolutely no plan for what he is to do next. None. He fumbles in his pockets for something. "Uhhh, here." He grabs the first thing in his pocket.

It's the cord from his Camp Half Blood necklace. There are no beads but the rope is recognizable.

"You're one of us?" The girl asks.

He holds out his hand, "Luke, son of Hermes. Pleased to meet you."

The others light up.

The younger boy seems the most excited, "I'm a son of Hermes too! My name's Travis!"

A younger brother! Luke found it hard to really connect with the sons of Mercury at Camp Jupiter. They all were different than him, more focused on trade than travel. A son of Hermes is different than one of Mercury. Hermes kids are so much better.

Luke grins, "It's nice to meet you little brother." He feels if they could talk for hours. Who knew that they would meet in a tiny diner in the middle of nowhere. 

The other two introduce themselves as a son of Aphrodite and a daughter of Demeter.

"If you're not at Camp Half Blood how have you survived for so long?" The older boy asks.

"I'm a son of Hermes, I always have a trick up my sleeve."

"My little brother Connor needs to meet you! We haven't had an older Hermes kid in the cabin for a long time." Travis speeds through the sentence. He is physically shaking.

This Luke is prepared for. He made nondescript business cards for this exact occasion. 

He hands one to Travis, "Call me if you ever need any help. I have a monster resistant cell on me at all times." Luke flashes the bulky Nokia to the demigods.

The girl pulls himself out of a daze. What are you doing here, shouldn't you be at Camp Half Blood?" 

Luke smiles wistfully, "There are some things that we should not know, this is one of them." With that cryptic message he leaves.

Luke's party of adventurers leave the parking lot without seeing the Greek demigods. Luke only hopes they won't need his help in the future. As usual his hope goes unfulfilled.

Nikki figures out here the second piece of the bracelet is: Glacier National Park, Montana. The three of them had previously been driving north until they had some idea in a typical demigod fashion.

Luke pays for their entrance with a wallet he pulled off an unfortunate bystander and the questing group is in. 

Of course the hidden lake is halfway up a mountain. And of course they have to fight off a bear. If it wasn't, Luke's life would be easy. He can't have that.

Gena puts the bracelet back together in a masterful display of skill on the lake shore. She really could have been put in the first cohort. Luke is glad she wasn't.

Venus appears to them over the lake and gives them a new bar for their tattoos. She also goes over a story about the time she cheated on Gena's father with Luke's father. Every day Luke is glad he made the deal with Chronos.

All Luke can do is watch her ramble.

Now they just need to get home. That would be easier if they didn't have multiple puncture wounds. Luke takes the chance to curse the gods once again.

A park ranger tells them that there has been a bear in the area when they come down the mountain. Nikki assures the man that they can handle it.

For the first time, Luke brings back both of his questmates. This is a time for celebration. Fireworks, food, and much fanfare. The festivities last a full day and for once, it is an untainted victory.

His own father visits. Hermes delivers a gift: Sneakers that fly when Luke shouts the names of Hermes’ mother.

It is a gift that would have been useful for his last two quests.

After everything Luke goes to see Lauren. The girl smiles as he approaches. He's glad to see she isn't hurt.

"Want a pretzel?" He asks.

She seems moderately surprised as if she thought he had forgotten about her, "Sure!"

"I was wondering how you are doing." He starts.

"Fine," she nods. "Camp missed you." She is avoiding the question.

Luke looks at her.

She gives in, "Why didn't you choose me? I was great last time, I just got injured. I don't understand. I don't understand." She rests her head in her hands.

Luke puts his hand on her shoulder, "Lauren, I didn't want you to get hurt. I watched your recovery, I couldn't make you go through that again."

The girl smiles weakly. "Thanks Luke. Just know that if you ever need anything, you can always ask."

"Actually," Luke pauses, "There is one thing I have been meaning to tell you about."

The two talk until the middle of the night. In a completely unrelated incident, he is appointed the new praetor the next morning.

Luke has never paid much attention to the fifth cohort. But there is an eleven year old in there that has just caught his eye. A son of Jupiter, Luke thought was just a rumor. After Octavian he should know that rumors always have a bit of truth to them.

The kid wants to bring it back to it's former glory. He's called Jason—after the legendary hero. Luke had never heard his full name until earlier that day. Jason Grace, the little brother of Thalia.

It is shocking to meet her previously thought dead little brother safe and sound. That only begs the question why did he live and she die?

But none of Luke's questions are answered these days. So he moves on with his life. The boy can wait until later.

In his first order for a long time, Kronos orders Luke to create a quest for the Golden Fleece in the sea on monsters. Luke convinces—no, threatens—Octavian to send a few kids from the first cohort to retrieve it.

Luke is pleased to see they succeed. Of course, the camp thinks it goes missing a few weeks later. Luke thinks it makes a great blanket.

Of course every action has a reaction.

He gets a call at midnight from an unknown number.

The person on the other end is breathing heavily and Luke swears that is from sobs. 

“Hello?” Luke asks.

There’s a sniffle from the other person. He speaks, “My brother told me to call this person if anything bad happened.”

“Who is your brother?”

The answer is quiet, “Travis Stoll.”

“Oh no,” Luke breathes. Out of all of the people he has met, he has liked Travis the most. He pauses, “Where is Travis?”

Connor sounds desperate, “He’s dead!” The boy’s words collapse into sobs.

“Connor, where are you?” Luke almost shouts it into the phone.

Connor breaks out of crying to tell the older demigod, “Eastern Washington a town called Clayton, please help me.” The boy’s voice breaks.

Luke scribbles down the answer. “I’m coming, Connor, hang in there.”

Not one person questions Luke as he leaves a note for his other praetor, and confiscates a Camp Jupiter SUV.

The drive is long, and Luke is tired, but he makes it there before ten am and he is willing to call that a victory.

Connor is easy to spot.

The boy is sitting in the parking lot of one of the local motels wearing a mildly bloodied orange Camp Half Blood t-shirt. A celestial bronze sword sits in his lap. He doesn’t look okay and he certainly doesn’t look over twelve.

Luke puts his sword in its holster and walks over to the kid.

Connor startles, bringing up the sword above his head in a pitiful attempt at protection.

“Woah woah woah,” Luke tries to calm the kid, “I’m Luke. You called me last night.”

Connor sets down the sword with a sigh and buries his head in his hands. Now that Luke is up close, he can see how tired the boy looks.

“Kid, you alright? Do you need me to check your wounds?”

The boy nods.

Luke grabs the med kit from his car and leads Connor inside. He isn’t hurt too badly, but he could get an infection if Luke doesn’t clean him up right now.

He tucks his half-brother into bed. They have a long day of questing tomorrow.

Luke comes up with the plan to defeat the drakon, and surprisingly, it works. He should put more faith in himself. Both him and Connor survive the quest with Connor only breaking his arm.

He offers to drive Connor back, but the boy says his brother Chris is leading a party back to get him. 

Luke elects to wait with the kid until they get there. He has a lot to discuss with them.

Camp Jupiter takes a trip to Mount Olympus that winter. This sort of thing doesn’t happen often for them, so the camp makes it a weeklong trip with lots of stops along the way.

It is the only chance for Luke to perform a task given to him. And Luke is not one to waste opportunities.

That spring is awfully chaotic for the camp. With Jupiter angry about the loss of the master bolt and lots of new campers, Luke has a lot on his plate. He needs to share the burden.

The other praetor is named John and the two of them have endured quite a few biblical jokes in their times as praetors.

Luke really likes the guy. He's a son of Venus and doesn't let it define him. Not to mention he is an even harder worker than Luke himself. John is an all around golden boy.

The two of them are on a late night walk near the sea post war games when Luke's reality hits him again. He's Greek and a servant of Kronos, yet he is a praetor of New Rome. His life is impossible. It could fall apart at any second.

Especially with what Kronos has ordered him to do.

Luke is overwhelmed. Their walk has slowed to a stop and Luke sits down on the edge of the cliff. It's not less dangerous than anything else in his life.

"Hey kid, are you okay?" John asks with the same even tone he says everything with. He sits down next to Luke.

"Yeah." Luke replies, "There's just something I have to do that I don't want to."

"Do you want to tell me about it?" John sounds so concerned that it hurts.

"No." Luke looks John in the eyes and does what he has to. “I do not.”

He watches his friend fall.

Their praetor's death is ruled an accident, after all, the most common cause of death for those in New Rome is drowning and was discovered wearing a full suit of armor.

A week later Luke looks up from the many bars of his tattoo and caduceus to see Jason staring up at him.

“Do you want to hear a story about your sister?” Luke asks.

Jason shakes his head. The kid looks awfully sad, given that he didn’t even know the praetor.

The whole legion is mourning John. They need to go through a mourning period before they can appoint a new praetor. It is time for Luke it make his move, he finally has a strong enough following. He can feel Kronos egging him on.

Today is exactly four years to the day since he arrived at Camp Jupiter, it is also the day he is set to give a eulogy for John in front of the Senate.

Luke gives the kid a smile before getting up, "Don't worry kid, everything will be alright soon."

The walk to the Senate House feels as if it takes years. Every step an eternity. His celestial bronze sword feels as heavy as a boulder strapped to his belt. Luke waits for the crowd and his mind to calm. Every single doubt he has ever had passes through his head before he opens his mouth.

Luke turns the master bolt over in his hand and musters his strength, “I do not think I have properly introduced myself to you. My name is Luke Castellan, I am a son of Hermes. And I have a proposition for you from Saturn."

The senate erupts into chaos.

Luke watches.

**Author's Note:**

> Roman Luke is 100 times scarier than Greek Luke, change my mind.


End file.
